﻿#region License, Terms and Conditions
//
// Copyright (c) 2008, aspZone.com
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above copyright
//       notice, this list of conditions and the following disclaimer in the
//       documentation and/or other materials provided with the distribution.
//     * Neither the name of the <organization> nor the
//       names of its contributors may be used to endorse or promote products
//       derived from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY aspZone.com ``AS IS'' AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL <copyright holder> BE LIABLE FOR ANY
// DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Author(s):
//  John Rudolf Lewis (http://aspZone.com)
//
#endregion

using System;
using System.Collections.Generic;

namespace aspZone.Commerce.DataAccess
{
    public interface IRepository<T>
    {
        /// <summary>
        /// Gets an entity from the underlying data store. Returns null if not found.
        /// </summary>
        /// <remarks>
        ///  Returns null if the entity is not found.
        /// </remarks>
        /// <param name="id">the id of the desired entity</param>
        /// <returns>the entity if found, otherwise null</returns>
        T Get(object id);
        
        /// <summary>
        /// Loads an entity from the underlying data store. Throws exception if not found.
        /// </summary>
        /// <remarks>
        /// Throws an exception if the entity is not found.
        /// </remarks>
        /// <param name="id">the id of the desired entity</param>
        /// <returns>the entity</returns>
        T Load(object id);

        /// <summary>
        /// Finds all entities from the underlying data store.
        /// </summary>
        /// <returns>a list of entities</returns>
        IList<T> Find();

        /// <summary>
        /// Saves an entity to the underlying data store. (INSERT)
        /// </summary>
        /// <param name="entity">the entity to save</param>
        void Save(T entity);

        /// <summary>
        /// Updates an entity int he underlying data store. (UPDATE)
        /// </summary>
        /// <param name="entity">the entity to update</param>
        void Update(T entity);

        /// <summary>
        /// Saves or Updates an entity to the underlying data store. (INSERT or UPDATE)
        /// </summary>
        /// <remarks>
        /// For entities with auto-generated id's or version field only.
        /// </remarks>
        /// <param name="entity">the entity to save or update</param>
        void SaveOrUpdate(T entity);

        /// <summary>
        /// Deletes an entity from the underlying data store.
        /// </summary>
        /// <param name="entity">the entity to delete</param>
        void Delete(T entity);

        /// <summary>
        /// Commits all changes to the unit of work, write all changes to the underlying data store.
        /// </summary>
        void CommitChanges();

        /// <summary>
        /// Begins a transaction
        /// </summary>
        /// <param name="isolationLevel"></param>
        void BeginTransaction(System.Data.IsolationLevel isolationLevel);
        
        /// <summary>
        /// Commits a transaction
        /// </summary>
        void CommitTransaction();

        /// <summary>
        /// Rolls back a transaction
        /// </summary>
        void RollbackTransaction();

        /// <summary>
        /// Clears all entities, changes are thrown away.
        /// </summary>
        void Clear();
    }
}
